# locust777

////深度递归
//#include<stdio.h>
//int Fun(int n)
//{
//if(n == 5)
//	return 2;
//else
//	return 2 * Fun(n + 1);
//}
//int main()
//{
//int ret = Fun(2);
//printf("%d\n",ret);
//return 0;
//scanf("%d",ret);
//}

//字符串逆序 （递归实现）
#include<stdio.h>
int main()
{
char arr[] = "abcdef";
int sz = sizeof(arr)/sizeof(arr[0]);
int left = 0;
int right = sz - 2;
while(left<right)
{
char tmp = arr[left];
arr[right] = arr[right];
arr[right] = tmp;
left++;
right--;
}
scanf("%d",arr);
return 0;
}